U.S. Pat. No. 3,308,131 discloses a class of compounds, said to be useful as insecticides, having the general structural formula ##STR2## Compounds in which there is aliphatic unsaturation in R.sup.3 or R.sup.4 are specifically excluded from the disclosed class. It is true that some of the specifically excluded compounds are virtually useless as insecticides. One example is the compound 1-N,N-dimethylcarbamyl-3-cyclohexyl-5-propargylthio-1,2,4-triazole. Similar compounds with a trifluoromethyl substituent in 3-position are also generally lacking in insecticidal activity of any practical importance.
However, I have discovered a restricted group of highly active, useful insecticides among those excluded from the aforementioned patent which have the general structural formula ##STR3## in which R is 2-propynyl, allyl, 2-bromoallyl, 2-chloroallyl, 2-methylallyl, 2,3,3-trichloroallyl, or 1-methylallyl and R' is tert.butyl, propyl, cyclopropyl, isopropyl or 1-ethylpropyl.